# -*- coding: utf-8 -*- 
# @project : 《Atcoder》
# @Author : created by bensonrachel on 2021/11/15
# @File : 227.C - ABC conjecture.py
# 直接暴力求解，正面攻破，非DP。
N = int(input())
ans = 0

for a in range(1,N+1):
    if a*a*a > N :break
    for b in range(a,N+1):
        if a*b*b > N :break
        ans += N//(a*b) - b + 1

print(ans)